DESCRIPTION(provided by applicant): Chronic renal insufficiency (CRI) is an underrecognized and undertreated condition that is a "silent epidemic" in the US population. The primary objectives of the proposed prospective cohort study among patients with CRI are: (1) to examine risk factors for the rapid progression of chronic renal disease; and (2) to determine the incidence of and risk factors for cardiovascular disease (CVD). The secondary objectives are: (3) to investigate the relationship between urinary protein excretion and the subsequent progression of chronic renal disease and risk of CVD; (4) to assess prognostic factors among patients with CVD; (5) to estimate the incidence of malnutrition (e.g., anemia), comorbid conditions and total mortality; (6) to study change in health-related quality of life; (7) to collect biological specimens (including DNA materials) for further studies; and (8) to conduct subgroup analyses based on underlying cause of chronic renal disease, gender, race, and other important covariables. The proposed study will recruit 3,000 adult patients with CRI (a glomerular filtration rate [GFR] of 30-70 ml/min/1.73m2) from 6 Clinical Centers in the US. Patients? risk factors, renal function, and clinical and subclinical CVD will be measured at their baseline examination. Patients will be followed prospectively for an average of 5 years to assess progression of chronic renal disease, occurrence of CVD, and secondary outcomes. We propose to establish a Clinical Center to recruit >500 patients with CRI who meet study eligibility criteria; to measure risk factors and important co-variables among study participants; to obtain measures of GFR and indicators of subclinical CVD at the baseline and follow-up examinations; to collect data on clinical renal and CVD events during follow-up; to deliver data and specimens to the Data Coordinating Center or designated Central Laboratory or Reading Centers in a timely fashion; and to perform other functions as requested by the study protocol. The proposed study will provide important information regarding the natural history of and risk factors for progression of chronic renal disease and development of CVD among patients with CRI. Given the extensive experience of our investigative team in renal and CVD epidemiological research and the large untapped potential for recruitment of patients with CRI in our hospital population, we are confident that we will make substantial contributions to the proposed study.